Rearrange the digits in ⟨1263045⟩ to meet the rules below.
⟨6th 5th 4th 3rd 2nd 1st 0th⟩
✅Match
Jump(1,2) = 1
4th → 1
Jump(2,4) = 2
Jump(3,6) = 1
⛔Avoid
5th|4th|3rd|0th → 6
⟨ ⁵ᵗʰa ¹ˢᵗb ⟩, (ab)₁₀ ≥ 16
#125034_v2.2
┌───┬───┬───┬───┬───┬───┬───┐
│6th│5th│4th│3rd│2nd│1st│0th│▒
╞═══╪═══╪═══╪═══╪═══╪═══╪═══╡▒
Step 1 │ │ │ 1 │ │ │ │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 2 │ │ 0 │ 1 │ │ │ │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 3 │ 2 │ 0 │ 1 │ │ │ │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 4 │ 2 │ 0 │ 1 │ 4 │ │ │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 5 │ 2 │ 0 │ 1 │ 4 │ │ 5 │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 6 │ 2 │ 0 │ 1 │ 4 │ 6 │ 5 │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 7 │ 2 │ 0 │ 1 │ 4 │ 6 │ 5 │ 3 │▒
└───┴───┴───┴───┴───┴───┴───┘▒
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Proof of 2023-12-11 Q1(m=6)
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Notation: if nth -> a, then we write [nth] = a.
Plainly, our first step follows from ✅「4th → 1」. Next, to avoid ⛔「⟨ ⁵ᵗʰa ¹ˢᵗb ⟩, (ab)₁₀ ≥ 16」, we need [5th] <= 1, so [5th] = 0.
┌───┬───┬───┬───┬───┬───┬───┐
│6th│ 5■│ 4■│3rd│2nd│1st│0th│▒
╞═══╪═══╪═══╪═══╪═══╪═══╪═══╡▒
Step 1 │ │ │ 1 │ │ │ │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 2 │ │ 0 │ 1 │ │ │ │ │▒
└───┴───┴───┴───┴───┴───┴───┘▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
--- Idle ---
┌───┬───┬───┬───┬───┬───┬───┐
│ │ 2 │ 6 │ 3 │ │ 4 │ 5 │
└───┴───┴───┴───┴───┴───┴───┘
By ✅「Jump(1,2) = 1」, we have 2 = [6th] or [2rd]. The latter does not hold, for otherwise there is no way to match ✅「Jump(2,4) = 2」:
┌───┬───┬───┬───┬───┬───┬───┐
│6th│5th│4th│3rd│ 2▲│1st│0th│
╞═══╪═══╪═══╪═══╪═══╪═══╪═══╡
│ │ 0 │ 1 │ │ 2 │ │ │
└───┴───┴───┴───┴───┴───┴───┘
Consequently, we have 2 = [6th]. Then, using ✅「Jump(2,4) = 2」, we get
┌───┬───┬───┬───┬───┬───┬───┐
│ 6■│5th│4th│ 3■│2nd│1st│0th│▒
╞═══╪═══╪═══╪═══╪═══╪═══╪═══╡▒
│ │ 0 │ 1 │ │ │ │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 3 │ 2 │ 0 │ 1 │ │ │ │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 4 │ 2 │ 0 │ 1 │ 4 │ │ │ │▒
└───┴───┴───┴───┴───┴───┴───┘▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
--- Idle ---
┌───┬───┬───┬───┬───┬───┬───┐
│ │ │ 6 │ 3 │ │ │ 5 │
└───┴───┴───┴───┴───┴───┴───┘
Note that ✅「Jump(3,6) = 1」 implies {3,6} = {[2nd], [0th]}. Therefore, 5 = [1st].
┌───┬───┬───┬───┬───┬───┬───┐
│6th│5th│4th│3rd│2nd│ 1■│0th│▒
╞═══╪═══╪═══╪═══╪═══╪═══╪═══╡▒
Step 4 │ 2 │ 0 │ 1 │ 4 │ │ │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 5 │ 2 │ 0 │ 1 │ 4 │ │ 5 │ │▒
└───┴───┴───┴───┴───┴───┴───┘▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
--- Idle ---
┌───┬───┬───┬───┬───┬───┬───┐
│ │ │ 6 │ 3 │ │ │ │
└───┴───┴───┴───┴───┴───┴───┘
Lastly, to avoid ⛔「5th|4th|3rd|0th → 6」, we finish by
┌───┬───┬───┬───┬───┬───┬───┐
│6th│5th│4th│3rd│ 2■│1st│ 0■│▒
╞═══╪═══╪═══╪═══╪═══╪═══╪═══╡▒
│ 2 │ 0 │ 1 │ 4 │ │ 5 │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 6 │ 2 │ 0 │ 1 │ 4 │ 6 │ 5 │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 7 │ 2 │ 0 │ 1 │ 4 │ 6 │ 5 │ 3 │▒
└───┴───┴───┴───┴───┴───┴───┘▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
--- Idle ---
┌───┬───┬───┬───┬───┬───┬───┐
│ │ │ │ │ │ │ │
└───┴───┴───┴───┴───┴───┴───┘
Q.E.D.
#125034_v2.2